MPI_Intercomm_create function

Creates an intercommuncator from two intracommunicators.

Syntax

int MPIAPI MPI_Intercomm_create(
        MPI_Comm local_comm,
        int      local_leader,
        MPI_Comm peer_comm,
        int      remote_leader,
        int      tag,
  _Out_ MPI_Comm *newintercomm
);

Parameters

• local_comm
  Local (intra)communicator.

• local_leader
  Rank in local_comm of leader (often 0).

• peer_comm
  Communicator used to communicate between a designated process in the other communicator. Significant only at the process in local_comm with rank local_leader.

• remote_leader
  Rank in peer_comm of remote leader (often 0).

• tag
  Message tag to use in constructing intercommunicator; if multiple MPI_Intercomm_create are being made, they should use different tags (more precisely, ensure that the local and remote leaders are using different tags for each MPI_Intercomm_create).

• newintercomm [out]
  Created intercommunicator.

Return value

Returns MPI_SUCCESS on success. Otherwise, the return value is an error code.

In Fortran, the return value is stored in the IERROR parameter.

Fortran

    MPI_INTERCOMM_CREATE(LOCAL_COMM, LOCAL_LEADER, PEER_COMM, REMOTE_LEADER, 
            TAG, NEWINTERCOMM, IERROR)
        INTEGER LOCAL_COMM, LOCAL_LEADER, PEER_COMM, REMOTE_LEADER, TAG,
        NEWINTERCOMM, IERROR

Requirements

See also

MPI Communicator Functions